A Summary of Progress in Petrography. in 1887-1896 |
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Page 1885
... plagioclase , and of an orthorhombic pyroxene , in which are porphyritic crystals of labradorite , a large quantity of biotite , columnar crystals of bronzite , hornblende , augite , and cordierite . The last - named mineral occurs in ...
... plagioclase , and of an orthorhombic pyroxene , in which are porphyritic crystals of labradorite , a large quantity of biotite , columnar crystals of bronzite , hornblende , augite , and cordierite . The last - named mineral occurs in ...
Page 1893
... plagioclase , and of an orthorhombic pyroxene , in which are porphyritic crystals of labradorite , a large quantity of biotite , columnar crystals of bronzite , hornblende , augite , and cordierite . The last - named mineral occurs in ...
... plagioclase , and of an orthorhombic pyroxene , in which are porphyritic crystals of labradorite , a large quantity of biotite , columnar crystals of bronzite , hornblende , augite , and cordierite . The last - named mineral occurs in ...
Page 1901
... plagioclase , apatite , hornblende , leucoxene , tourmaline and quartz are all described and figured . Between the hornblende schists and the Laurentian gneisses the author recognizes phenomena which he believes to be due to contact ...
... plagioclase , apatite , hornblende , leucoxene , tourmaline and quartz are all described and figured . Between the hornblende schists and the Laurentian gneisses the author recognizes phenomena which he believes to be due to contact ...
Page 1
... plagioclase and sericite , with a breccia - like structure produced by pressure . The quartz and plagio- clase are shattered , and the broken pieces are reunited by a cement of secondary quartz and sericite . The second is a chlorite ...
... plagioclase and sericite , with a breccia - like structure produced by pressure . The quartz and plagio- clase are shattered , and the broken pieces are reunited by a cement of secondary quartz and sericite . The second is a chlorite ...
Page 9
... plagioclase . The lack of plagioclase places the rock in the group of the limburgites . The rocks from the crater of the Cañadas are also basalts , whose olivines are filled with muscovitic in- clusions . Large crystals of andesine ...
... plagioclase . The lack of plagioclase places the rock in the group of the limburgites . The rocks from the crater of the Cañadas are also basalts , whose olivines are filled with muscovitic in- clusions . Large crystals of andesine ...
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Common terms and phrases
acute bisectrix Al,O Amer AMERICAN NATURALIST amphibole analysis andesites apatite augite axial ratio basalt biotite bisectrix brown Bull calcite Colby University color colorless composition containing cordierite corresponding described diabase diorites double refraction dykes Edited by Dr epidote eruptive Fe,O feldspar FeO CaO MgO FeO MnO Förh formula gabbro garnet Geol gneiss grains granite green ground-mass H₂O hardness hexagonal hornblende inclusions isomorphous Jour Kryst Lacroix lamellæ lithophysæ lustre magma magnetite MAKERS SYRACUSE manganese mica microlites mineral occurs MINERALOGY AND PETROGRAPHY.¹ molecule monoclinic Na,O Na₂O nepheline Neues Jahrb olivine optical angle optical axes original orthoclase orthorhombic Petrog PETROGRAPHY.¹ Petrographical phenocrysts plagioclase pleochroic porphyritic porphyritic crystals pressure prismatic produced pyroxene quartz regarded resembles rhombohedral rocks scapolite schists silica small crystals specific gravity spherulites structure substance symmetry thin section tion twinning plane variety W. S. Bayley Waterville yellow yielded Zeits
Popular passages
Page 5 - The olivine is surrounded by a reactionary rim consisting of an inner zone of hypersthene and an outer one of actinolite.